fix: read owner GVK from object metadata instead of scheme

The operator does not know the CNPG API group at runtime (it is
not a sidecar injected by the CNPG operator, so CUSTOM_CNPG_GROUP
and CUSTOM_CNPG_VERSION are not available). Move SetControllerReference
to the specs package and read the GVK from the decoded Cluster's
TypeMeta rather than looking it up in the scheme.

Remove CNPG types from the operator's scheme and the env var bindings
from cmd/operator since they are no longer needed.

Signed-off-by: Marco Nenciarini <marco.nenciarini@enterprisedb.com>

internal/cmd/operator/main.go

@@ -102,8 +102,6 @@ func NewCmd() *cobra.Command {
 	_ = viper.BindPFlag("server-address", cmd.Flags().Lookup("server-address"))
 
 	_ = viper.BindEnv("sidecar-image", "SIDECAR_IMAGE")
-	_ = viper.BindEnv("custom-cnpg-group", "CUSTOM_CNPG_GROUP")
-	_ = viper.BindEnv("custom-cnpg-version", "CUSTOM_CNPG_VERSION")
 
 	return cmd
 }

internal/cnpgi/operator/manager.go

@@ -37,33 +37,24 @@ import (
 
 	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
 	"github.com/cloudnative-pg/plugin-barman-cloud/internal/controller"
-	pluginscheme "github.com/cloudnative-pg/plugin-barman-cloud/internal/scheme"
 
 	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
 	// to ensure that exec-entrypoint and run can make use of them.
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
 )
 
-// generateScheme creates a runtime.Scheme with all type definitions
-// needed by the operator. CNPG types are registered under a
-// configurable API group to support custom CNPG-based operators.
-func generateScheme(ctx context.Context) *runtime.Scheme {
-	result := runtime.NewScheme()
+var scheme = runtime.NewScheme()
 
-	utilruntime.Must(clientgoscheme.AddToScheme(result))
-	utilruntime.Must(barmancloudv1.AddToScheme(result))
-	pluginscheme.AddCNPGToScheme(ctx, result)
+func init() {
+	utilruntime.Must(clientgoscheme.AddToScheme(scheme))
+	utilruntime.Must(barmancloudv1.AddToScheme(scheme))
 	// +kubebuilder:scaffold:scheme
-
-	return result
 }
 
 // Start starts the manager
 func Start(ctx context.Context) error {
 	setupLog := log.FromContext(ctx)
 
-	scheme := generateScheme(ctx)
-
 	var tlsOpts []func(*tls.Config)
 
 	// if the enable-http2 flag is false (the default), http/2 should be disabled

internal/cnpgi/operator/rbac/doc.go

@@ -0,0 +1,22 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+// Package rbac contains utilities to reconcile RBAC resources
+// for the barman-cloud plugin.
+package rbac

internal/cnpgi/operator/rbac/ensure.go

@@ -17,8 +17,6 @@ limitations under the License.
 SPDX-License-Identifier: Apache-2.0
 */
 
-// Package rbac contains utilities to reconcile RBAC resources
-// for the barman-cloud plugin.
 package rbac
 
 import (
@@ -31,7 +29,6 @@ import (
 	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/client-go/util/retry"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 
 	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
 	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/metadata"
@@ -106,7 +103,7 @@ func ensureRoleExists(
 		return err
 	}
 
-	if err := controllerutil.SetControllerReference(cluster, newRole, c.Scheme()); err != nil {
+	if err := specs.SetControllerReference(cluster, newRole); err != nil {
 		return err
 	}
 

internal/cnpgi/operator/rbac/ensure_test.go

@@ -49,6 +49,10 @@ func newScheme() *runtime.Scheme {
 
 func newCluster(name, namespace string) *cnpgv1.Cluster {
 	return &cnpgv1.Cluster{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: cnpgv1.SchemeGroupVersion.String(),
+			Kind:       cnpgv1.ClusterKind,
+		},
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      name,
 			Namespace: namespace,

internal/cnpgi/operator/reconciler.go

@@ -30,7 +30,6 @@ import (
 	rbacv1 "k8s.io/api/rbac/v1"
 	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	"sigs.k8s.io/controller-runtime/pkg/client"
-	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 
 	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
 	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/operator/config"
@@ -163,7 +162,7 @@ func (r ReconcilerImplementation) createRoleBinding(
 	cluster *cnpgv1.Cluster,
 ) error {
 	roleBinding := specs.BuildRoleBinding(cluster)
-	if err := controllerutil.SetControllerReference(cluster, roleBinding, r.Client.Scheme()); err != nil {
+	if err := specs.SetControllerReference(cluster, roleBinding); err != nil {
 		return err
 	}
 	return r.Client.Create(ctx, roleBinding)

internal/cnpgi/operator/specs/ownership.go

@@ -0,0 +1,59 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package specs
+
+import (
+	"fmt"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/utils/ptr"
+)
+
+// SetControllerReference sets an owner reference on controlled
+// pointing to owner, reading the GVK from the owner object's
+// metadata rather than from a scheme. This is necessary because
+// the operator does not know the CNPG API group at compile time
+// (it may be customized), while the Cluster object decoded from
+// the gRPC request carries the correct GVK in its TypeMeta.
+func SetControllerReference(owner, controlled metav1.Object) error {
+	ro, ok := owner.(runtime.Object)
+	if !ok {
+		return fmt.Errorf("%T is not a runtime.Object, cannot call SetControllerReference", owner)
+	}
+
+	gvk := ro.GetObjectKind().GroupVersionKind()
+	if gvk.Kind == "" {
+		return fmt.Errorf("%T has no GVK set in its metadata, cannot call SetControllerReference", owner)
+	}
+
+	controlled.SetOwnerReferences([]metav1.OwnerReference{
+		{
+			APIVersion:         gvk.GroupVersion().String(),
+			Kind:               gvk.Kind,
+			Name:               owner.GetName(),
+			UID:                owner.GetUID(),
+			BlockOwnerDeletion: ptr.To(true),
+			Controller:         ptr.To(true),
+		},
+	})
+
+	return nil
+}

internal/cnpgi/operator/specs/ownership_test.go

@@ -0,0 +1,90 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package specs
+
+import (
+	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	rbacv1 "k8s.io/api/rbac/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+)
+
+var _ = Describe("SetControllerReference", func() {
+	It("should set the owner reference from the owner's TypeMeta", func() {
+		owner := &cnpgv1.Cluster{
+			TypeMeta: metav1.TypeMeta{
+				APIVersion: "postgresql.cnpg.io/v1",
+				Kind:       "Cluster",
+			},
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "my-cluster",
+				Namespace: "default",
+				UID:       types.UID("test-uid"),
+			},
+		}
+		controlled := &rbacv1.Role{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "my-role",
+				Namespace: "default",
+			},
+		}
+
+		Expect(SetControllerReference(owner, controlled)).To(Succeed())
+		Expect(controlled.OwnerReferences).To(HaveLen(1))
+		Expect(controlled.OwnerReferences[0].APIVersion).To(Equal("postgresql.cnpg.io/v1"))
+		Expect(controlled.OwnerReferences[0].Kind).To(Equal("Cluster"))
+		Expect(controlled.OwnerReferences[0].Name).To(Equal("my-cluster"))
+		Expect(controlled.OwnerReferences[0].UID).To(Equal(types.UID("test-uid")))
+		Expect(*controlled.OwnerReferences[0].Controller).To(BeTrue())
+		Expect(*controlled.OwnerReferences[0].BlockOwnerDeletion).To(BeTrue())
+	})
+
+	It("should work with a custom CNPG API group", func() {
+		owner := &cnpgv1.Cluster{
+			TypeMeta: metav1.TypeMeta{
+				APIVersion: "mycompany.io/v1",
+				Kind:       "Cluster",
+			},
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "my-cluster",
+				UID:  types.UID("test-uid"),
+			},
+		}
+		controlled := &rbacv1.Role{}
+
+		Expect(SetControllerReference(owner, controlled)).To(Succeed())
+		Expect(controlled.OwnerReferences[0].APIVersion).To(Equal("mycompany.io/v1"))
+	})
+
+	It("should fail when the owner has no GVK set", func() {
+		owner := &cnpgv1.Cluster{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "my-cluster",
+			},
+		}
+		controlled := &rbacv1.Role{}
+
+		err := SetControllerReference(owner, controlled)
+		Expect(err).To(HaveOccurred())
+		Expect(err.Error()).To(ContainSubstring("has no GVK set"))
+	})
+})

internal/scheme/cnpg.go

@@ -17,8 +17,6 @@ limitations under the License.
 SPDX-License-Identifier: Apache-2.0
 */
 
-// Package scheme provides utilities for building runtime schemes
-// with support for custom CNPG API groups.
 package scheme
 
 import (

internal/scheme/doc.go

@@ -0,0 +1,22 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+// Package scheme provides utilities for building runtime schemes
+// with support for custom CNPG API groups.
+package scheme